Seeing Gravity Waves

Here at Screaming Circuits, we assemble PCBs for a lot of interesting organizations. Perhaps one of the most interesting is LIGO (Laser Interferometer Gravity Wave Observatory). In case you've been busy with Pokemon GO for the last few months, and missed the announcement, in February, LIGO announced the first ever detection of gravity waves.

Back in April, I visited the LIGO lab at MIT, and in July, I went to South Central Washington and toured one of the detector sites. Over the years, we've built electronics for both locations. The other two locations are another lab at CalTech, and another detector installation in Louisiana. The image on the right shows the Squeezed vacuum experiment being developed at the MIT lab.

Gravity waves were predicted by Einstein 100 years ago, and confirmed with this detection. Since the first announcement, LIGO has seen two more events. One has been confirmed as another gravity wave, the other, they're still not quite sure. In the words of my tour guide at LIGO Hanford: "It walks like a duck, talks like a duck, but doesn't quite smell like a duck."

Here's a view in the control room at the Hanford site:

One of the detector arms. This isn't the actual detector tube. You're seeing the concrete tunnel protecting the tube. The light path goes through a steel tube kept at a near perfect vacuum (one trillionth of an atmosphere). Their tumbleweed mitigation equipment is in the foreground.

Duane BensonNo, Doc. Nothing happened to the earth's gravitational field